/*
 * Copyright (c) 1997, 2018 Oracle and/or its affiliates. All rights reserved.
 * Copyright 2005-2007 The Apache Software Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package javax.faces.view.facelets;

import javax.faces.view.EditableValueHolderAttachedObjectHandler;

/**
 * <p class="changed_added_2_0">Handles setting a {@link
 * javax.faces.validator.Validator} instance on an {@link
 * javax.faces.component.EditableValueHolder} parent. Will wire all
 * attributes set to the <code>Validator</code> instance
 * created/fetched. Uses the "binding" attribute for grabbing instances
 * to apply attributes to.</p> 

 * <p>Will only set/create Validator is the passed UIComponent's parent
 * is null, signifying that it wasn't restored from an existing
 * tree.</p>

 */
public class ValidatorHandler extends FaceletsAttachedObjectHandler implements EditableValueHolderAttachedObjectHandler {

    private String validatorId;
    
    private TagHandlerDelegate helper;

    private ValidatorConfig config;


    /**
     * <p class="changed_added_2_0">Construct this instance around the configuration information in argument <code>config</code></p>
     * @param config the <code>TagConfig</code> subclass for this kind
     * of attached object.
     */
    public ValidatorHandler(ValidatorConfig config) {
        super(config);
        this.config = config;
        this.validatorId = config.getValidatorId();
    }

    /**
     * <p class="changed_added_2_0">Return the implementation specific
     * delegate instance that provides the bulk of the work for this
     * handler instance.</p>
     * 
     * @return the implementation specific delegate instance
     */
    @Override
    protected TagHandlerDelegate getTagHandlerDelegate() {
        if (null == helper) {
            helper = delegateFactory.createValidatorHandlerDelegate(this);
        }
        return helper;
    }

    /**
     * <p>Retrieve the id of the validator that is to be created and
     * added to the parent <code>EditableValueHolder</code>.  All
     * subclasses should override this method because it is important
     * for Facelets to have a unique way of identifying the validators
     * that are added to this <code>EditableValueHolder</code> and
     * allows exclusions to work properly. An exclusion is a validator
     * declaration that has the attribute "disabled" which resolves to
     * false, instructing Facelets not to register a default validator
     * with the same id.</p>
     * 
     * @param ctx the FaceletContext for this {@code Facelet}
     * 
     * @return the validator-id
     */
    public String getValidatorId(FaceletContext ctx) {
        if (validatorId == null) {
            TagAttribute idAttr = getAttribute("validatorId");
            if (idAttr == null) {
                return null;
            } else {
                return idAttr.getValue(ctx);
            }
        }
        return validatorId;
    }


    /**
     * <p class="changed_added_2_0">Return the <code>TagConfig</code>
     * subclass used to configure this handler instance.</p>
     * 
     * @return the <code>TagConfig</code> subclass used to configure this handler instance.
     */
    public ValidatorConfig getValidatorConfig() {

        return config;
        
    }

}
